Marking instrument



FIG. 1 is a perspective view showing my new design;

FIG. 2 is a perspective view showing the side not shown in FIG. 1;

FIG. 3 is a top plan view;

FIG. 4 is a side elevational view, the opposite side being a mirror image thereof;

FIG. 5 is a bottom plan view;

FIG. 6 is an end elevational view;

FIG. 7 is an elevational view showing the end opposite that shown in FIG. 6. 

An ornamental design for a marking instrument, as shown and described. 